Update:
Injector constant is fine, car does indeed have a 4 bar FPR, this has to be a fueling table issue. I bring down maximum VE to under 190% and it fuels perfectly. Now the "tuning" begins.

My thought is to get my fueling table for wot proper for the maximum boost I intend to achieve and let it interpolate under that. Looks like the top of this table was set up that way only for maybe 20psi instead of 18. I'm scared of 20 psi and there's no reason why I should be going there with my turbo unless I feel like pushing the same volume of much warmer air into my intake, sacrificing timing and turbo bearings for no reason..

Any takers on what to look out for or am I completely off base with this approach?